Merge #90

90: turn macros into attributes r=adamgreig a=japaric

This is a PoC implementation of RFC #82. Assuming that we are OK with this implementation we should
add some compile fail tests (e.g. using a function with the wrong signature as the entry point)
before landing this.

Look at the diff of the examples to get an overview of the changes.

cc @rust-embedded/cortex-m

Co-authored-by: Jorge Aparicio <jorge@japaric.io>

1 files changed, 6 insertions, 6 deletions

diff --git a/cortex-m-rt/examples/state.rs b/cortex-m-rt/examples/state.rs
index dbacdaf..573914f 100644
--- a/cortex-m-rt/examples/state.rs
+++ b/cortex-m-rt/examples/state.rs
@@ -5,20 +5,20 @@
 #![no_main]
 #![no_std]
 
-#[macro_use(entry, exception)]
 extern crate cortex_m_rt as rt;
 extern crate panic_semihosting;
 
-// the program entry point
-entry!(main);
+use rt::{entry, exception};
 
+#[entry]
 fn main() -> ! {
     loop {}
 }
 
 // exception handler with state
-exception!(SysTick, sys_tick, state: u32 = 0);
+#[exception]
+fn SysTick() {
+    static mut STATE: u32 = 0;
 
-fn sys_tick(state: &mut u32) {
-    *state += 1;
+    *STATE += 1;
 }